As electronic devices used in terrestrial industrial instruments or on-board industrial instruments mounted in, e.g., airplanes, for example, there is an electronic device using an electronic circuit substrate formed in conformity to a VME standard, which is a standard of Versa Module Europe (VME). In this electronic device, the electronic circuit substrate is inserted into a substrate attachment portion of a rack type housing formed in conformity to the VME standard and attached to the same in this state. Electronic components such as an electronic module, a power amplifier, a filter, and others are installed on the electronic circuit substrate. Such electronic components generate heat when used.
Generally, in an electronic device used in terrestrial industrial instruments, heat generated by electronic components disposed to an electronic circuit substrate based on the VME standard is efficiently cooled by natural air convection or forced air convection. On the other hand, in space where an on-board industrial instrument mounted in, e.g., aerospace-related devices, airplanes is used, air convection is not produced. Therefore, in an electronic device used in the on-board industrial instrument, a plurality of column supports are provided to protrude on an electronic circuit substrate, and a radiation heat sink is disposed to the column supports on the electronic circuit through fixation screws. The heat generated by electronic components installed on the electronic circuit substrate is conducted to a rack type housing through the heat sink. As a result, the heat generated by the electronic components is radiated.